The overhead-line based DC transmission is becoming the developing trend of flexible DC transmission because of the breakthrough of the converter-based DC fault isolating technique. The probability of nonpermanent faults on the overhead line is very large

thus the restart scheme should be configured to increase the supply reliability. However

the conventional restart scheme will lead to the second overcurrent or overvoltage damages

which is detrimental to the safe operation of the system. This paper proposes a novel restart scheme

which makes the converter operate as an uncontrolled rectifier

then the fault property can be determined according to the current characteristic of the DC line. Compared with the conventional restart scheme

the overcurrent and overvoltage problems during the restarting period could be avoided effectively. Finally

cases in point are used via the PSCAD/EMTDC to verify the feasibility and superiority of the proposed restart scheme. This work is supported by National Natural Science Foundation of China(No. 51677126)and China Southern Power Grid Company Limited(No. CSGTRC-K163001).